// Without doing this in a finally block (at least with the mini cluster),
// the region server never goes down.
// mark the batch as having been written. In the single-update case, this never gets check
// again, but in the batch case, we will check it again (see above).
ikv.markBatchFinished();
// release the lock on the index, we wrote everything properly
// we took the lock for each Put/Delete, so we have to release it a matching number of times
// batch cases only take the lock once, so we need to make sure we don't over-release the
// lock.